A. Field of the Invention
The embodiments of the present invention relate to a self-latching sector motor, and more particularly, the embodiments of the present invention relate to a self-latching sector motor for producing a net torque from one of two integral sources that may permit either source to be used as the primary torque producer, permits either source to be used redundantly or as a spare backup, permits paralleling sources for doubling output torques, or permits alternate use of sources to avoid overheating effects.
B. Description of the Prior Art
In critical applications, a redundant coil capability is an important asset. A redundant coil capability provides back-up, or when paralleled, doubles net torque.
Numerous innovations for motors have been provided in the prior art, which will be described below in chronological order to show advancement in the art, and which are incorporated herein by reference thereto. Even though these innovations may be suitable for the individual purposes to which they address, nevertheless, they differ from the present invention in that they do not teach a self-latching sector motor for producing a net torque that can be backed-up or doubled.
(1) U.S. Pat. No. 3,761,851 to Nelson.
U.S. Pat. No. 3,761,851 issued to Nelson on Sep. 25, 1973 in U.S. class 335 and subclass 253 teaches a two-pole armature located between two field poles, which provides a direct motion rotary actuator with high starting torque and angular rotation over substantially any angle less than 180°. Latching, non-latching, fail-safe return motion, and tailored torque are a few of the many possible modes of operation. Rotary actuators are widely used devices for providing angular motion over predetermined angles. The most common devices are called rotary solenoids, since they convert linear solenoid action to rotary motion. Rotary solenoids have a number of limitations and undesirable characteristics even though they have been the subject of intensive development and are used in large quantities. Rotary solenoids are inefficient and noisy. Starting torque is low and ending torque is high—just the opposite to that of an ideal device.
(2) U.S. Pat. No. 3,970,980 to Nelson.
U.S. Pat. No. 3,970,980 issued to Nelson on Jul. 20, 1976 in U.S. class 335 and subclass 253 teaches a rotary actuator that has rotation of its rotor over predetermined angles. The rotor is a cylindrical housing in which are cylindrically curved permanently-magnetized poles, spaced-apart at their ends and surrounding a fixed armature. The armature has magnetic arms angularly disposed with respect to each other, which define fixed poles. Coils wound on the fixed poles generate magnetic fields when energized to drive the rotor. A holding coil is provided to hold the rotor stationary when the holding coil is energized. The armature has two, three, or more fixed poles. The actuator is operated in rotor latching or fail-safe return modes. Fixed stop members are used to limit angular rotation of the rotor.
(3) U.S. Pat. No. 4,500,861 to Nelson.
U.S. Pat. No. 4,500,861 issued to Nelson on Feb. 19, 1985 in U.S. class 335 and subclass 253 teaches a sector motor having a rotor that is rotatable to one of three positions in a housing. The rotor carries field magnets surrounding stationary armature poles carried by the housing. An arcuate 90° slot in one end of the housing receives an arcuate 45° arm projecting from the rotor, thereby limiting the rotor to a total angular rotation of 90°. Spaced latching magnets coact in mutual repulsion or attraction or both to latch the rotor at either end of rotor rotation. The motor's inherent magnetic restoring force, assisted by a magnetic detent carried by the housing and rotor and located midway between opposite ends of the 90° slot, latch and prevent vibration of the rotor in a central position between opposite ends of its range of rotation.
(4) U.S. Pat. No. 4,795,929 to Elgass et al.
U.S. Pat. No. 4,795,929 issued to Elgass et al. on Jan. 3, 1989 in U.S. class 310 and subclass 36 teaches a rotary actuator in which there is a freely rotatable permanent magnetic armature between two stators. At least one of the stators produces an asymmetrical magnetic flux field that acts upon the magnetic field of the armature to cause the same to rotate.
(5) U.S. Pat. No. 4,847,526 to Takehara et al.
U.S. Pat. No. 4,847,526 issued to Takehara et al. on Jul. 11, 1989 in U.S. class 310 and subclass 185 teaches an electric motor in which one motor element—either the stator or rotor—has magnetic poles whose effective magnetic width is substantially equal and which span equal center angles. The second motor element has a plurality of armature groups, each of which occupies a phase sector of the motor element formed by dividing the total periphery by a natural number. All of the armatures within an armature group are connected electrically in series and excited with a current of one phase—either an alternating current phase or an equivalent phase generated by commutator action. Within one pole group, the poles have equal widths or different widths.
(6) United States Patent Application Publication Number US 2002/0093265 A1 to Nelson.
United States Patent Application Publication Number US 2002/0093265 A1 published to Nelson on Jul. 18, 2002 in U.S. class 310 and subclass 192 teaches a continuous rotation or a multi-position actuator. The continuous rotation armature has at least two poles spaced-apart from the armature and a third pole that is adjustable in distance from the armature. The multi-position actuator includes a housing, an armature rotatably mounted in the housing, and a series of poles journaled around the armature. There is also a stop arm attached to the armature, which stops the rotation of the armature when the stop arm hits an adjacent stop. These stops are positioned within the housing to limit the rotation of the armature. This multi-position actuator is designed to form either a fail safe actuator or a latching actuator by adjusting the spacing of the air gap between the poles and the armature. The fail safe actuator is designed so that the stop arm attached to the armature is positioned between the stops when the poles are not charged. When the poles are charged, however, the armature rotates so that the stop arm turns to contact one of the adjacent stops. When power is removed, the armature rotates back to its original position, with the stop arm being positioned between the two stops. The latching actuator is designed so that the armature may be positioned at one of three different positions and then remain there when no power is applied to the poles. When power is applied to the poles, however, the armature rotates to the designated position and remains there even after power has been removed.
(7) U.S. Pat. No. 6,518,685 B2 to Nelson.
U.S. Pat. No. 6,518,685 B2 issued to Nelson on Feb. 11, 2003 in U.S. class 310 and subclass 191 teaches a multi-position actuator with three electromagnetic poles, wherein the air gap of selected pole(s) is made different from the remaining pole(s). The multi-position actuator includes a housing, an armature rotatably mounted in the housing, and three poles journaled around the armature. There is also a stop arm attached to the armature, which stops the rotation of the armature when the stop arm hits an adjacent stop. These stops are positioned within the housing to limit the rotation of the armature. This multi-position actuator is designed to form either a fail safe actuator or a latching actuator by adjusting the spacing of the air gap between the poles and the armature. When used with continuous rotation without the stop mechanism, the air gap(s) of the pole(s) can be adjusted in a repetitive manner to produce a useful magnetic torque.
(8) United States Patent Application Publication Number US 2004/0021390 A1 to Kim et al.
United States Patent Application Publication Number US 2004/0021390 A1 published to Kim et al. on Feb. 5, 2004 in U.S. class 310 and subclass 191 teaches a permanent-magnet-type synchronous-rotary-electric machine that includes a stator provided with windings. A rotor, arranged to be supported for rotation in the stator with a gap between the inner surface of the stator and the outer surface thereof is divided into two rotor bodies, each provided with permanent magnets of opposite polarities alternately arranged in a circumferential direction. In switching the permanent-magnet-type synchronous-rotary-electric machine from a motor to a generator, a second rotor body is moved axially relative to a first rotor body to an axial position that makes the intensity of a combined magnetic field created by the permanent magnets lower than that of a combined magnetic field created by the permanent magnets when the second rotor body is located at a predetermined position, and then the second rotor body is moved to the predetermined position.
(9) U.S. Pat. No. 6,967,422 B2 to Nelson.
U.S. Pat. No. 6,967,422 B2 issued to Nelson on Nov. 22, 2005 in U.S. class 310 and subclass 191 teaches a two-position rotary actuator that provides a latching or holding torque that can be adjusted by altering the magnetic properties of a selected pole member. The actuator also functions as a sector motor over a selected range of angular motion, and provides failsafe operation that returns the actuator to a starting position when electrical power is removed.
(10) United States Patent Application Publication Number US 2009/0261680 A1 to Oki et al.
United States Patent Application Publication Number US 2009/0261680 A1 published to Oki et al. on Oct. 22, 2009 in U.S. class 310 and subclass 195 teaches a stator core that includes a plurality of salient pole portions that are formed in a radial shape, are wound with a stator coil, and are disposed at a uniform angle except for a non-equiangular pitch region, a circular outer peripheral yoke formed so as to be continuous with the outer peripheral side of the salient pole portions, a cut-out that is formed by cutting out part of the outer peripheral yoke in an approximate sector-shape except in the non-equiangular pitch region of the salient pole portions, and a compensating pole plate that is provided in the cut-out along the ends on the inner peripheral side of the non-equiangular pitch region where the salient pole portions are formed.
(11) United States Patent Application Publication Number US 2009/0295251 A1 to Vollmer et al.
United States Patent Application Publication Number US 2009/0295251 A1 published to Vollmer et al. on Dec. 3, 2009 in U.S. class 310 and subclass 195 teaches a permanently excited synchronous machine, which includes a rotor and a stand that contains a three-branched winding system that includes tooth coils. The stand has a total of three or six grooves, and a tooth is formed therebetween. A total of three tooth coils are arranged in the grooves, and each coil is associated with one of the three winding phases. The number of user pole pairs is four or five. The rotor has twice as many user pole pairs of permanent magnets that are evenly distributed on the periphery.
It is apparent that numerous innovations for motors have been provided in the prior art, which are adapted to be used. Furthermore, even though these innovations may be suitable for the specific individual purposes to which they address, however, they would not be suitable for the purposes of the embodiments of the present invention as heretofore described, namely, a self-latching sector motor for producing a net torque that can be backed-up or doubled.